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SYNTHESIS, STRUCTURES, ELECTRONIC STRUCTURES AND PHYSICAL PROPERTIES OF QUATERNARY ALKALI, ALKALINE EARTH, RARE EARTH AND TRANSITION METAL PNICTIDES by Yi Wang A thesis submitted to the Faculty of the University of Delaware in partial fulfillment of the requirements for the degree of Master of Science in Chemistry and Biochemistry Summer 2015  2015 Yi Wang All Rights Reserved ProQuest Number: 1602360 All rights reserved INFORMATION TO ALL USERS The quality of this reproduction is dependent upon the quality of the copy submitted. In the unlikely event that the author did not send a complete manuscript and there are missing pages, these will be noted. Also, if material had to be removed, a note will indicate the deletion. ProQuest 1602360 Published by ProQuest LLC (2015). Copyright of the Dissertation is held by the Author. All rights reserved. This work is protected against unauthorized copying under Title 17, United States Code Microform Edition © ProQuest LLC. ProQuest LLC. 789 East Eisenhower Parkway P.O. Box 1346 Ann Arbor, MI 48106 - 1346 SYNTHESIS, STRUCTURES, ELECTRONIC STRUCTURES AND PHYSICAL PROPERTIES OF QUATERNARY ALKALI, ALKALINE EARTH, RARE EARTH AND TRANSITION METAL PNICTIDES by Yi Wang Approved: __________________________________________________________ Svilen S. Bobev, Ph.D. Professor in charge of thesis on behalf of the Advisory Committee Approved: __________________________________________________________ Murray V. Johnston, Ph.D. Chair of the Department of Chemistry and Biochemistry Approved: __________________________________________________________ George H. Watson, Ph.D. Dean of the College of Arts and Sciences Approved: __________________________________________________________ James G. Richards, Ph.D. Vice Provost for Graduate and Professional Education ACKNOWLEDGMENTS Foremost, I would like to express the deepest appreciation to my advisor Dr. Bobev for giving me the opportunity to study in his laboratory. His infectious passion and professional attitude have been major driving forces through my graduate career in the University of Delaware. I am extremely grateful for his guidance, suggestions and persistent help in these years. Without his important contribution this thesis would not have been possible. I would like to thank the Department of Chemistry and Biochemistry at University of Delaware for the financial support. And my sincere thanks also go for Dr. Burmeister for his help, understanding and offering my summer teaching opportunity in the Department. I would like to thank the past and current members of Dr. Bobev’s group, Dr. Hua He, Dr. Nian-Tzu Suen, Dr. Marion Schäfer, Dr. Jiliang Zhang, Dr. Stanislav Stoyko, Dr. Julien Makongo, Mr. James Hoos, Mr. Matt Broda and Mr. Greg Darone. They always support and help me in different ways and I really learn lots of experiences and experimental skills from them. In addition I would like to thank all researchers, technicians, and staffs, who provide all kinds of support and help for me, especially to Dr. Yap, who helps me with single- crystal X-ray diffractometer and Robert Schmidt, who helps me with Physical Property measurement system (PPMS) measurements. And a thank you to all my friends in the department of Chemistry and Biochemistry, I really appreciate their help and cherish our friendships and time we spent together. iii Last but not least, I would like to acknowledge with the love and support of my family—my parents Jianping Wang and Yiling Li and my husband Bin Fang. They all keep me going through my life. Without their care and love, I could be who I am right now. iv TABLE OF CONTENTS LIST OF TABLES……………………………………………………………………….vii LIST OF FIGURES……………………………………………………………………….ix ABSTRACT.......................................................................................................................xi Chapter 1 INTRODUCTION……………...…………………………………………………1 1.1 Background…………………………………………………………………..1 1.2 Intermetallic Compounds and Zintl Phases………………………………….2 1.3 Cation Effect and Exploratory Studies of Quaternary Pnictides with Alkali- Alkaline Earth or Rare-Earth Metals and Transition Metals…………..……6 1.4 Layout of The Thesis………………………………………………….....….8 REFERENCES………………………………………………………………..…10 2 QUATERNARY PNICTIDES WITH COMPLEX, NONCENTROSYMMETRIC STRUCTURES. SYNTHESIS AND STRUCTURAL CHAACTERIZATION OF THE NEW ZINTL PPASES Na Ca Al Sb , Na CaGaSb , AND 11 2 3 8 4 3 Na Ca In Sb …………………………………………………………………...12 15 3 5 12 2.1 Abstract……………………………………………………………………..12 2.2 Introduction…………………………………………………………………13 2.3 Experimental………………………………………………………………..14 2.4 Results and Discussion...................................................................................18 2.5 Conclusions…………………………………………………………………27 REFERENCES……………………………………………………………….….39 3 EFFICIENT TAILORING OF BAND GAP INDUCED BY RARE EARTH (RE) METALS DOPINGDETERMINING STRUCTURE AND PROPERTIES OF NARROWGAP SEMICONDUCTOR Ca RE Mn Sb (RE = La, Ce, Pr, Nd 9-x x 4 9 AND Sm)……………………………………………………………………...…42 3.1 Abstract…………………………………………………………………..…42 3.2 Introduction………………………………………………………………....42 3.3 Experimental……………………………………………………..…………44 3.4 Results and Discussion…………………………………………..…………48 3.5 Conclusions.…………………………………………..………………….…58 REFERENCES…………………….………………….…………………………75 4 CONLUSIONS……………………………………………..………………..…..79 v 4.1 Brief Summary of This Work…………………………………….………...79 4.2 Future Prospects…………………………………………………………….79 REFERENCES…………………………………………………………………..80 Appendix A A HANDY LIST OF EIGHT NEW COMPOUNDS AND THEIR SPACE GROUP INFORMATION……………………………………………………...…………81 B REPRINT PERMISSION LETTERS……………………………………….…….82 vi LIST OF TABLES Table 2.1: Selected Single-Crystal Data Collection and Structure Refinement Parameters for Na Ca Al Sb , Na CaGaSb , and Na Ca In Sb …........29 11 2 3 8 4 3 15 3 5 12 Table 2.2: Atomic Coordinates and Equivalent Isotropic Displacement Parameters U eq for Na Ca Al Sb ……………………………………………………......30 11 2 3 8 Table 2.3: Atomic Coordinates and Equivalent Isotropic Displacement Parameters U eq for Na CaGaSb ………………………………………………………….31 4 3 Table 2.4: Atomic Coordinates and Equivalent Isotropic Displacement Parameters U eq for Na Ca In Sb ……………………………………………………….32 15 3 5 12 Table 2.5: Selected Interatomic Distances (Å) And Angles (degree) in Na Ca Al Sb , 11 2 3 8 Na CaGaSb , and Na Ca In Sb ….…………………………………….33 4 3 15 3 5 12 Table 3.1: Selected Crystal Data and Structure Refinement Parameters for Ca La Mn Sb ………………………………………………......59 8.27(1) 0.73(1) 4 9 Table 3.2: Selected Crystal Data and Structure Refinement Parameters for Ca Ce Mn Sb ………………………………………………......60 8.16(1) 0.84(1) 4 9 Table 3.3: Selected Crystal Data and Structure Refinement Parameters for Ca Pr Mn Sb …………………………………….…………......61 8.15(1) 0.85(1) 4 9 Table 3.4: Selected Crystal Data and Structure Refinement Parameters for Ca Nd Mn Sb …………………………………………….….....62 8.11(1) 0.89(1) 4 9 Table 3.5: Selected Crystal Data and Structure Refinement Parameters for Ca Sm Mn Sb ………………………………………………......63 7.88(1) 1.12(1) 4 9 Table 3.6: Atomic Coordinates and Equivalent Isotropic Displacement Parameters (U ) for Ca La Mn Sb ……………………………………..…...64 eq 8.27(1) 0.73(1) 4 9 Table 3.7: Atomic Coordinates and Equivalent Isotropic Displacement Parameters (U ) for Ca Ce Mn Sb …………….………………….………..65 eq 8.16(1) 0.84(1) 4 9 Table 3.8: Atomic Coordinates and Equivalent Isotropic Displacement Parameters (U ) for Ca Pr Mn Sb ……………………………….…………66 eq 8.15(1) 0.85(1) 4 9 Table 3.9: Atomic Coordinates and Equivalent Isotropic Displacement Parameters (U ) for Ca Nd Mn Sb ……………………………………....…67 eq 8.11(1) 0.89(1) 4 9 Table 3.10: Atomic Coordinates and Equivalent Isotropic Displacement Parameters (U ) for Ca Sm Mn Sb …………………………………...……68 eq 7.88(1) 1.12(1) 4 9 vii Table 3.11: Important Interatomic Distances (Å) and Angles (degree) for Ca La Mn Sb and Ca Sm Mn Sb ……………..........…69 8.27(1) 0.73(1) 4 9 7.88(1) 1.12(1) 4 9 Table 3.12: Comparison between Measured and Expected Effective Moments in Ca RE Mn Sb series (RE= La, Ce, Pr, Nd and Sm)…………………… 70 9-x x 4 9 viii LIST OF FIGURES Figure 2.1: Polyhedral views of the structures of Na Ca In Sb (a), Na CaGaSb (b), 15 3 5 12 4 3 and Na Ca Al Sb (c). The common atomsCa, Na, and Sb-are drawn as 11 2 3 8 blue, green, and orange spheres, respectively. The atoms centering the Sb tetrahedra-In, Ga, and Al-are shown in light blue, pink, and red, respectively…………………..……………………………………….….34 Figure 2.2: Detailed drawings in different orientations of a [In Sb ] cutout from the 4 12 layers of the Na Ca In Sb structure (a), a [Ga Sb ] cutout from the 15 3 5 12 4 13 chains in the Na CaGaSb structure (b), and the [Al Sb ] cluster in the 4 3 3 8 Na Ca Al Sb structure (c). The atoms are labeled, and the relevant 11 2 3 8 distances and angles are listed in Table 1.5……………………………….34 Figure 2.3: Polyanionic substructures of Na CaGaSb (a) and Na Ca Al Sb (b) 4 3 11 2 3 8 viewed as tetrahedral “hybrid layers”, made up of Ga, Na, Sb and Al, Na, Sb, respectively. The atoms are labeled, and the relevant distances are listed in Table 1.5……………………………………………………………….35 Figure 2.4: Structural relationships among Na Ca In Sb , Na CaGaSb , and 15 3 5 12 4 3 Na Ca Al Sb . Panel (a) shows the idealized, defect-free [InSb ] 11 2 3 8 2 polyanionic layers in Na Ca In Sb ; panel (b) depicts the hypothetical 15 3 5 12 hybrid [Ga Na Sb ] layers in Na CaGaSb ; panel c shows the imaginary 2/3 1/3 2 4 3 [Al Na Sb ] layers in Na Ca Al Sb . In all drawings, two different 1/2 1/2 2 11 2 3 8 orientations are shown, with the tetrahedra rendered in green corresponding to the NaSb units………………………………………………………...36 4 Figure 2.5: Structural relationships among Na In Bi (TiNiSi structure type) [36] and 3 2 3 Na Ca In Sb , Na CaGaSb , and Na Ca Al Sb . Panel (a) shows the 15 3 5 12 4 3 11 2 3 8 three-dimensional framework of the parent structure with Na shown in yellow, In shown in blue, and Bi shown in orange. Panels (b)-(d) depict the structures of Na Ca In Sb , Na CaGaSb , and Na Ca Al Sb , where the 15 3 5 12 4 3 11 2 3 8 frameworks include the tetrahedrally coordinated Na atoms. To guide the eye, the In−Sb, Ga−Sb, and Al−Sb bonds are colored with the respective elemental colorsblue, pink, and redand the Na−Sb “bonds” are drawn as gray cylinders……………..……..…………………………………….....37 Figure 2.6: Calculated total and partial DOS curves for Na Ca In Sb (a), 15 3 5 12 Na CaGaSb (b), and Na Ca Al Sb (c). The Fermi level is the energy 4 3 11 2 3 8 reference at 0 eV………………………………………………………….38 Figure 2.7: COHP curves for In−Sb, Ga−Sb, and Al−Sb (black lines) and for selected Na−Sb interactions (red lines). Panel (a) refers to Na Ca In Sb , panel (b) 15 3 5 12 refers to Na CaGaSb , and panels (c) and (d) refer to Na Ca Al Sb . In 4 3 11 2 3 8 plots of the COHP curves, the COHP values were inverted (i.e., −COHP is shown) so that the positive and negative regions represent bonding and ix

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I am extremely grateful for his guidance, suggestions and persistent help in Julien Makongo, Mr. James Hoos, Mr. Matt Broda and Mr. Greg Darone.
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